The present invention relates to brake hangers for railway vehicles, and it more particularly relates to a brake hanger permitting a greater than normal lateral movement of an associated brake shoe within the elastic limits of the hanger.
It is well known that there is some periodic lateral movement of a railway truck relative to the truck wheels, and early patents have disclosed brake hangers that bend to permit limited lateral movement of the brake shoes during braking relative to a truck frame to which the hangers are pivotally secured. Such a hanger is disclosed, for example, in the U.S. Pat. No. 1,166,521, granted Jan. 4, 1916. The hanger according to this patent is formed of bar stock in the shape of a closed or an open link, with the laterally spaced sides of the hanger being forged to be substantially flat for bending more readily in response to lateral movement of the truck frame relative to the wheels. Such repeated bending tends to crystalize the sides of the hanger, causing them to create a safety hazard by breaking and permitting the brake rigging to drop on the trackway in front of a wheel to possibly cause derailment.
These shortcomings are discussed in U.S. Pat. No. 1,509,907, granted Sept. 30, 1924, which provides an improved structure in the form of an articulated hanger requiring ball joint connections at the upper and lower ends of the hanger to prevent bending of substantially rigid laterally spaced side arms of the hanger. These ball joint connections, however, require extra maintenance, and may themselves be sources of breakage upon the freezing up of the joints, and the like.
An object of the present invention is to provide an improved brake hanger which substantially obviates one or more of the limitations of the described prior art hangers.
Another object of the present invention is to provide an improved integral brake hanger that is flexible laterally to accomodate a substantially greater lateral movement of a railway brake head within the elastic limits of the hanger.
Other objects, purposes and characteristic features of the present invention will be in part obvious from the accompanying drawing, and in part pointed out as the description of the invention progresses.